I am 12 weeks pregnant and everytime i wipe i see brown pieces liver like substance for 2 days and now has a bit red in it. is this a miscarriage.

12 weeks pregnant: What you describe may reflect inadequate progesterone made by the placenta after ovarian cessation of progesterone production, so see your OB immediately for a quantitative HCG test, and supplemental progesterone if the test is compatible with 12 weeks of pregnancy. Ask for a pelvic sonogram to confirm placental location, as well.